Core C, the Statistics Core, provides data archiving and methodological expertise for the current project. There are three specific aims to the core: 1) Provide a data archiving and maintenance function;2) Provide statistical consultation and data analysis, as well as methodological consultation;and 3) Provide educational opportunities for project investigators. Each of these aims is critical to the successful execution of the current project. The data archiving function allows investigators to safely store data and promotes collaborative relationships when common outcomes or predictor variables are examined. The statistical consulting and methodological design aim represents the major function of this core and allows investigators to design and execute better experiments, as well as it allows investigators to have access to the most current statistical treatments for their data. Finally, the educational aim allows investigators to stay abreast of current developments in statistical methodology in order for them to consider their application in their own research.